Are miscompares a problem?

I burnt onto a DVD (as a data disk) 2 folders containing at most 100 files each, one mds file, one mdf file (3.99GB), and one md0 (340mb) file. This all comes out to 4.5gb. I used CDBurnerXP to burn these files, but the verification would have taken 600 minutes so instead I dled another program to do the verification (namely IMG Burner).

So i used the program to verify the dvd to the image file I have on my PC and I get over 90,000 miscompares. However, when I just check for "read errors" there are no problems shown.

So my questions are: What exactly are miscompare errors? and lastly, in this situation, does it warrant me to reburn the disc (and/or keep the img on my PC as a backup just in case) or should I just leave it as it is (if there are no problems) and delete the 4.5 gb worth of files from my compute to clear up some space (only got 12 gigs free on my 150 gb HDD)

If you get 90,000 miscompares then most likely that image isn't the same that was burned on the disc. Try comparing the files on the disc against the source files with something like Beyond Compare or similar.